Nuclear power can generate electricity without greenhouse gas emissions. However, there are concerns about its safety. Learn about the safety and health concerns associated with the threat of nuclear meltdowns, as well as the challenges involved in storing radioactive waste.he isotope U-235 is important because it can be used in the nuclear fission chain reaction to create a lot of energy. Unlike the uranium used in a nuclear bomb, which is about 90% enriched with the isotope U-235, the uranium used in a nuclear reactor is only slightly enriched, to about four or five percent.
1 Professional sod installation typically costs $500 to $1,000 for a 2,000 sq. ft. or smaller lawn. 2  Per square foot installation costs average $.50 to $1.00. 3  Installing sod on smaller lawns tends to cost more per square foot.
1 For the do-it-yourselfer, rolls of sod cost 8-30 cents a square foot, depending on the variety and quantity bought. 2  For front and back lawns of 20x50 feet each, that's 2,000 square feet or $160-$600. For front and back lawns of 20x50 feet each, that's 2,000 square feet or $160-$600. 2  Having sod professionally installed just about doubles the cost to 14-60 cents a square foot, or $280-$1,000 for 2,000 square feet.